To say that the HTC One (M8) is a powerful phone is a bit of an understatement. As much as we try to bring it to its knees, the phone holds its head high and accomplishes the task at hand without breaking a sweat. But does the phone’s raw processing power get in the way of endurance?

Over the years, HTC has given us few phones with outstanding battery life. Last year’s HTC One max got praised for its lasting power, but that’s only because the massive size of the phone allowed HTC to equip the phone with a 3,300 mAh battery. The phone could easily get through two full days of use with 6-8 hours of screen-on time. The new HTC one (M8) comes with smaller 2,600 mAh battery. It’s not much of a bump form the 2,300 mAh battery HTC crammed into the HTC one (M7), but the 13% increase in capacity makes a much bigger impact than we were expecting.

The Full Day Phone

If you consider yourself a power user, the HTC One (M8) may be the first flagship device to give you a full day’s use. On our highest use day, we managed to kill the HTC One (M8) in just under 12 hours. But that’s the worst case scenario. Over the past 16 days, we’ve managed to use the phone 12 full days (from the time we woke up until the time we went to sleep) without worrying about the phone’s battery charge. On most days, the battery still had 15-20% charge. We also spent a few days to see just how long we could extend the life of the phone by not playing any games, capturing pictures of watching video. We finally plugged the HTC One (M8) into its charger after 39 hours. the remaining 3% charge could have gotten up to the 40 hour mark, but the One (M8) had already proven its point.

The incredible lasting power of the HTC One (M8) is partly credited to the larger 2,600 mAh battery, but the Qualcomm Snapdragon 801 and HTC’s software optimization should be commended as well. Qualcomm’s newer chip is a lot more power efficient than the Snapdragon 600 that was used to power last year’s HTC One, allowing for infinitesimal power draw when the phone is not in use.

Media and gaming junkies will appreciate the HTC One (M8). When all four of the Snapdragon 801 cores on the phone are engaged while playing graphic intensive games, power draw does increase quite bit. But it’s not as noticeable as it is on other devices. Don’t be surprised if the phone’s power level drops 20% after an hour of intense gaming, but more casual games like Threes, Droid Rage or Flappy Bird have a significantly lesser impact on the One (M8)’s battery.

Power Saver

Those who don’t do a lot of gaming will definitely want to check out HTC’s Power Saver mode. When turned on, Power Saver gives you the option to underclock the processor, reduce screen brightness, turn off the vibration motor and cut the phone’s data connection when the display is turned off. The feature turns on automatically when the phone’s power level reaches 20%, but you have the option to use it all the time. With Power Save engaged and a 100% charge, the HTC One (M8) should easily be able to hit 50 hours with light use.

Extreme Power Saver

One of the features HTC is most proud of on the HTC One (M8) is Extreme Power Saver. How many times have you glanced at your phone only to see that you have 4% battery left? By the time you turn down your screen brightness and switch the phone into Airplane Mode, the splash screen shows up, informing you that your phone is officially out of commission.

With Extreme Power Saver mode, HTC claims that the One (M8) can last up to 15 hours on a 5% charge. Enable Extreme Power Saver mode with a 100% charge and the phone will theoretically last over 10 days. But don’t think for a second that you’ll have access to any of the features that make the HTC One (M8) a smartphone when Extreme Power Saver mode is turned on. Flip the Extreme Power Saver mode switch and you’re greeted with a bare UI that only lets you access the Phone, Messaging (SMS), Email, Calendar, Calculator and Clock apps. Everything else it gated off. You don’t even have a notification bar at the top to pull down.

We haven’t been able to test it out for ourselves, because the software feature isn’t yet available on the Verizon, T-Mobile and AT&T models of the One (M8) here in the US. Sprint pushed out an update for its version of the HTC One (M8) a few days ago, which included Extreme Power Saver mode, so we expect other carrier branded devices will get it in the coming weeks. We’ll share our results once we spend some quality time with the feature.

Conclusion

The HTC One (M8)’s lasting power isn’t in the same league as the Samsung Galaxy Note 3, HTC One max or any of Motorola’s MAXX phones, but the phone doesn’t claim to be. HTC has equipped the HTC One (M8) with a battery that gives enough power that you can go through a full day without ever worrying about finding the nearest outlet. Yes, the battery may last you less than 10 hours if you’re constantly watching YouTube clips or trying to beat The Walking Dead in a single session, but that’s pretty much par for the course. The HTC One (M8) may be ushering us into the era of the full-day phone.

Nick is a tech enthusiast who has a soft spot for HTC and its devices. He started HTCsource.com (the first HTC blog) back in 2007 and later joined the Android and Me family in the summer of 2010.

The Extreme Power Saver Mode can be sideloaded/flashed in an S-OFF Verizon unit. I’ve tested it out. It basically strips the interface down to a black & white page with: (1) phone; (2) messaging; (3) calendar; (4) email and (5) calculator. You can’t manipulate/access the status bar (although I think you can respond to notifications). You can’t load the app drawer or run any other apps. Vibration is eliminated and the screen is slightly dimmed. I haven’t tested the effect on battery, because, to tell the truth, battery life is wonderful with just the power savings currently available on the VZW unit.

what does it matter if the phone battery lasts 30days without charge.. when you can not use the phone because of the bad mics that HTC puts in them… google htc one and microphone issues.
the htc 1 m7 had them and the htc 1 m8 has the SAME exact issues…
htc lost a customer in me… samsung will eventually put htc out of business :) and thank god..

….and by that time m8 will be viewed as a prehistoric phone and owners will be well overdue for an upgrade. That is, non-removable batteries are only an issue if you keep the same phone for several years or treat the existing battery badly e.g. charging often when it is no where near depletion.

HTC use higher quality Lithium batteries than you get in your Korean plastic trash. You can get 1000 charges with only 10% loss of capacity, whereas you’ll be lucky to get much more than a year from A Samsung battery without significant loss.
In any case Samsung fanboy, there’s no bloated, stuttering, memory hog TouchWiz to kill the battery on the M8!
Go and troll somewhere else idiot, this is an HTC site for people who actually know something about tech, not for you sheep…

@Nick: Nicely done article, Nick. Like Dima I’ve always been partial to Samsung, especially because of their brilliant screens & replaceable batteries. I’ve had friends that have owned both HTC & LG and the screen on my Samsung always seemed to be more crystal clear, sharper, brighter, etc. But from what I’m seeing from HTC lately, they appear to really be stepping up to bat. Another selling pt for Samsung is the replaceable / swappable battery. I typically carry a spare where ever I go so I’m never without. Whereas the other brands, even if I carried an A/C adapter, I’d still need to find an A/C outlet, which isn’t always available. Still, HTC is very impressive.

That’s actually rather a matter of taste, than quality. Samsung’s amoled screens were up ’til the S4 very greenish and white wasn’t really white. They did better introducing the S4, but Samsung also has a thing for making their screens extra colorful. Some people like this and think it looks extra appealing. Others prefer colors to be true. HTC has always done a finer job on that. Both brands offer great quality, it all comes down to taste.

The problem is that for all android phones the (low) battery usage you get in the 1st mo or so does not continue and by the 6mo mark the 18hr phone only lasts 12. Thats why I will stick to phones that have swapable batteries.

I am not talking about Battery degradation – I am talking about application/OS issues that seem to result in many android phones (stock non-rooted non-managed = regular people) slowing down and getting poorer and poorer battery life over time.

Good to see these newer processors are so powerful, yet don’t eat into the battery life much. Battery life is one area that is always good to be improving, and glad Htc has seemed to figured it out with the one.

“If you consider yourself a power user, the HTC One (M8) may be the first flagship device to give you a full day’s use.”

I’m assuming you mean the M8 is the first HTC flagship phone to get you through a day, since the Note line and the G2 get through the day with plenty to spare at the end of the day.

Good to hear they were able to get that kind of battery performance out of 2600 mah. But honestly, with all of that bezel and the increased height of the device I’m surprised they couldn’t cram a 3000 mah battery in it.

Just a thought. All these people who are willing to carry around extra batteries, can’t carry a portable usb charger? I’m sorry but this removable battery argument just seems so redundant. You would rather compromise on your device for that removable battery but refuse to carry around a portable charger? Crazy

I’m not as concerned with battery life as much as battery longevity. Being a bit of a gear-head I have owned countless cell phones, PDA’s, media players, etc, etc. Every single one that used a rechargeable battery regardless of battery technology eventually got to the point where the original battery stopped taking a charge. Without exception. I would love to get an M8, but it’s just too expensive of a device to have a sealed-in, non-replaceable battery. This device ought to remain useful for two to four years given the more or less future-proof spec. It obviously won’t be cutting-edge for that long but it should remain useful enough to pass on to a family member or sell to recoup some value for the next coveted gadget. Sadly, it won’t though. Unless HTC has managed to escape the laws of physics, this phone will have a non-charging battery within a couple years, or at the very least a battery with DRASTICALLY REDUCED talk time. Maybe someone will invent a cottage industry for replacing toasted embedded batteries…

I still have my HTC One S from two years ago and it’s working just fine. Yes, battery performance degradation over time is a real thing, but battery technology has gotten a lot better. My HTC One S still gets 8-10 hours on a single charge when I’m using it as a daily driver. Back when it was new, I would have been lucky to get 12 hours out of it.

I’d still like a spare replacement Battey and the option to charge my fone at my Leisure without these policy handcuffs. Why I cannot choose to change the Battey and buy additional Batteries is beyond me. It’s just one idea short of genius. Shame, cos I don’t like spending time sitting by the charger, maybe your designers do. I like choice.

Using a S3, started off with using a portable charger, it is painful, to wait for it to slowly charge, having to hold the charger while I use the phone, very inconvenient and bulky.

I switched to use replaceable batteries, it’s awesome. Bought a spare battery and a battery charger for 10 bucks from China. Every morning go out with 2 full batts. When one is down, it takes ten seconds to get your phone to 100 percent , no hassle.

I tried an S5 but the battery lasted a few hours under normal use, half a day. Less than my S3. Swapped out for an M8 (was within return window with vendor) and the battery is lasting 2 days under normal use. Far better than my S3 was. Feels good in the hand to hold and generally use. HTC have done a nice job overall with build, look and feel and useability. Their Sense6, in my opinion, is not too far removed from the vanilla android and has come a long way since its early days.

i’m traveling now and using my htc one and it is killing me. 2 hours of moderate use and i’m at 50% battery. can’t even charge on laptop coz it will go usb drive mode. I WISH THE COMPANY WILL BANKRUPT SOON. seriously, i used to defend htc and now I WISH THE COMPANY WILL BANKRUPT SOON.

My M7 has always been a full day smartphone. Like the article says, you can use any of brand hard enough for it to need charging early in the afternoon. I usually go to sleep at night with 20-30% charge remaining and I’m usually up every day at 5:30-6 AM and rarely go to bed before midnight.

The Extreme Power Saver Mode can be sideloaded/flashed in an S-OFF Verizon unit. I’ve tested it out. It basically strips the interface down to a black & white page with: (1) phone; (2) messaging; (3) calendar; (4) email and (5) calculator. You can’t manipulate/access the status bar (although I think you can respond to notifications). You can’t load the app drawer or run any other apps. Vibration is eliminated and the screen is slightly dimmed. I haven’t tested the effect on battery, because, to tell the truth, battery life is wonderful with just the power savings currently available on the VZW unit.

what does it matter if the phone battery lasts 30days without charge.. when you can not use the phone because of the bad mics that HTC puts in them… google htc one and microphone issues.
the htc 1 m7 had them and the htc 1 m8 has the SAME exact issues…
htc lost a customer in me… samsung will eventually put htc out of business :) and thank god..

….and by that time m8 will be viewed as a prehistoric phone and owners will be well overdue for an upgrade. That is, non-removable batteries are only an issue if you keep the same phone for several years or treat the existing battery badly e.g. charging often when it is no where near depletion.

HTC use higher quality Lithium batteries than you get in your Korean plastic trash. You can get 1000 charges with only 10% loss of capacity, whereas you’ll be lucky to get much more than a year from A Samsung battery without significant loss.
In any case Samsung fanboy, there’s no bloated, stuttering, memory hog TouchWiz to kill the battery on the M8!
Go and troll somewhere else idiot, this is an HTC site for people who actually know something about tech, not for you sheep…

@Nick: Nicely done article, Nick. Like Dima I’ve always been partial to Samsung, especially because of their brilliant screens & replaceable batteries. I’ve had friends that have owned both HTC & LG and the screen on my Samsung always seemed to be more crystal clear, sharper, brighter, etc. But from what I’m seeing from HTC lately, they appear to really be stepping up to bat. Another selling pt for Samsung is the replaceable / swappable battery. I typically carry a spare where ever I go so I’m never without. Whereas the other brands, even if I carried an A/C adapter, I’d still need to find an A/C outlet, which isn’t always available. Still, HTC is very impressive.

That’s actually rather a matter of taste, than quality. Samsung’s amoled screens were up ’til the S4 very greenish and white wasn’t really white. They did better introducing the S4, but Samsung also has a thing for making their screens extra colorful. Some people like this and think it looks extra appealing. Others prefer colors to be true. HTC has always done a finer job on that. Both brands offer great quality, it all comes down to taste.

The problem is that for all android phones the (low) battery usage you get in the 1st mo or so does not continue and by the 6mo mark the 18hr phone only lasts 12. Thats why I will stick to phones that have swapable batteries.

I am not talking about Battery degradation – I am talking about application/OS issues that seem to result in many android phones (stock non-rooted non-managed = regular people) slowing down and getting poorer and poorer battery life over time.

Good to see these newer processors are so powerful, yet don’t eat into the battery life much. Battery life is one area that is always good to be improving, and glad Htc has seemed to figured it out with the one.

“If you consider yourself a power user, the HTC One (M8) may be the first flagship device to give you a full day’s use.”

I’m assuming you mean the M8 is the first HTC flagship phone to get you through a day, since the Note line and the G2 get through the day with plenty to spare at the end of the day.

Good to hear they were able to get that kind of battery performance out of 2600 mah. But honestly, with all of that bezel and the increased height of the device I’m surprised they couldn’t cram a 3000 mah battery in it.

Just a thought. All these people who are willing to carry around extra batteries, can’t carry a portable usb charger? I’m sorry but this removable battery argument just seems so redundant. You would rather compromise on your device for that removable battery but refuse to carry around a portable charger? Crazy

I’m not as concerned with battery life as much as battery longevity. Being a bit of a gear-head I have owned countless cell phones, PDA’s, media players, etc, etc. Every single one that used a rechargeable battery regardless of battery technology eventually got to the point where the original battery stopped taking a charge. Without exception. I would love to get an M8, but it’s just too expensive of a device to have a sealed-in, non-replaceable battery. This device ought to remain useful for two to four years given the more or less future-proof spec. It obviously won’t be cutting-edge for that long but it should remain useful enough to pass on to a family member or sell to recoup some value for the next coveted gadget. Sadly, it won’t though. Unless HTC has managed to escape the laws of physics, this phone will have a non-charging battery within a couple years, or at the very least a battery with DRASTICALLY REDUCED talk time. Maybe someone will invent a cottage industry for replacing toasted embedded batteries…

I still have my HTC One S from two years ago and it’s working just fine. Yes, battery performance degradation over time is a real thing, but battery technology has gotten a lot better. My HTC One S still gets 8-10 hours on a single charge when I’m using it as a daily driver. Back when it was new, I would have been lucky to get 12 hours out of it.

I’d still like a spare replacement Battey and the option to charge my fone at my Leisure without these policy handcuffs. Why I cannot choose to change the Battey and buy additional Batteries is beyond me. It’s just one idea short of genius. Shame, cos I don’t like spending time sitting by the charger, maybe your designers do. I like choice.

Using a S3, started off with using a portable charger, it is painful, to wait for it to slowly charge, having to hold the charger while I use the phone, very inconvenient and bulky.

I switched to use replaceable batteries, it’s awesome. Bought a spare battery and a battery charger for 10 bucks from China. Every morning go out with 2 full batts. When one is down, it takes ten seconds to get your phone to 100 percent , no hassle.

I tried an S5 but the battery lasted a few hours under normal use, half a day. Less than my S3. Swapped out for an M8 (was within return window with vendor) and the battery is lasting 2 days under normal use. Far better than my S3 was. Feels good in the hand to hold and generally use. HTC have done a nice job overall with build, look and feel and useability. Their Sense6, in my opinion, is not too far removed from the vanilla android and has come a long way since its early days.

i’m traveling now and using my htc one and it is killing me. 2 hours of moderate use and i’m at 50% battery. can’t even charge on laptop coz it will go usb drive mode. I WISH THE COMPANY WILL BANKRUPT SOON. seriously, i used to defend htc and now I WISH THE COMPANY WILL BANKRUPT SOON.

My M7 has always been a full day smartphone. Like the article says, you can use any of brand hard enough for it to need charging early in the afternoon. I usually go to sleep at night with 20-30% charge remaining and I’m usually up every day at 5:30-6 AM and rarely go to bed before midnight.